Landscape ecological risk assessment and its driving factors in the Weihe River basin,China

Weihe River basin is of great significance to analyze the changes of land use pattern and landscape ecological risk and to improve the ecological basis of regional development.Based on land use data of the Weihe River basin in 2000,2010,and 2020,with the support of Aeronautical Reconnaissance Coverage Geographic Information System(ArcGIS),GeoDa,and other technologies,this study analyzed the spatial-temporal characteristics and driving factors of land use pattern and landscape ecological risk.Results showed that land use structure of the Weihe River basin has changed significantly,with the decrease of cropland and the increase of forest land and construction land.In the past 20 a,cropland has decreased by 7347.70 km2,and cropland was mainly converted into forest land,grassland,and construction land.The fragmentation and dispersion of ecological landscape pattern in the Weihe River basin were improved,and land use pattern became more concentrated.Meanwhile,landscape ecological risk of the Weihe River basin has been improved.Severe landscape ecological risk area decreased by 19,177.87 km2,high landscape ecological risk area decreased by 3904.35 km2,and moderate and low landscape ecological risk areas continued to increase.It is worth noting that landscape ecological risks in the upper reaches of the Weihe River basin are still relatively serious,especially in the contiguous areas of high ecological risk,such as Tianshui,Pingliang,Dingxi areas and some areas of Ningxia Hui Autonomous Region.Landscape ecological risk showed obvious spatial dependence,and high ecological risk area was concentrated.Among the driving factors,population density,precipitation,normalized difference vegetation index(NDVI),and their interactions are the most important factors affecting the landscape ecological risk of the Weihe River basin.The findings significantly contribute to our understanding of the ecological dynamics in the Weihe River basin,providing crucial insights for sustainable management in the region.

Factors affecting land dissection density in geomorphological regions of China

Land dissection density(LDD)provides morphological evidence regarding prior intense soil erosion and quantifies the distribution of land dissections.A comprehensive understanding of the potential factors influencing the spatial pattern and value of the LDD is vital in geological disasters,soil erosion,and other related domains.Land dissection phenomena in China affects large areas with different morphological,pedological,and climatic characteristics.Prior studies have focused on the potential factors influencing the LDD at a watershed scale.However,these results are insufficient to reflect the status quo of dissection development and its primary influencing factors on a national scale.LDD’s spatial patterns and the dominant factors at a regional scale in millions of square kilometers remain to be ascertained.This study used the geomorphon-based method and the geographical detector model to quantify the spatial pattern of LDD over China and identify the dominant factors affecting this pattern in China’s six first-order geomorphological regions(GR1~GR6).The results yield the following findings:(1)LDD in China ranges from 0~4.55 km/km^(2),which is larger in central and eastern regions than in other regions of China;(2)dominant factors and their dominant risk subcategories vary with each geomorphological region’s primary internal and external forces;(3)the influence of natural factors is more significant on the large regional scale in millions of square kilometers compared to anthropogenic factors;relief degree of land surface(RDLS)is dominant in GR1,GR2,and GR5;the slope is dominant in GR6,soil type is dominant in GR3 and GR4,and lithology plays a critical role in the dominant interactions of GR3,GR4,and GR6;(4)the interactions between factors on LDD’s spatial pattern have a more significant effect than individual factors.

Exploring the Forest Cover Changes and Influential Factors of Dongsithouane National Production Forest Area, Savannakhet Province, Lao PDR

The Dongsithouane National Production Forest (DNPF) is one of the largest natural forest areas in Savannakhet, Lao PDR, which has been a vital support for the local community’s livelihood, Recently, significant changes in land use and land cover (LULC) have been observed in this area, leading to a reduction of natural forests. There were two separate methods of this study: firstly, to identify LULC changes across three different periods, spectral imagery from the Landsat 5 Thematic Mapper (TM) for the years 2001 and 2011, and the Landsat 8 Operational Land Imager (OLI) for 2021 were used as the primary data sources. The satellite images were preprocessed for various forest classes, including pretreatment of the top of atmosphere reflectance by using QGIS software’s semi-automatic classification plug-in (SCP), and ArcGIS was used for post-classification. A supervised classification approach was applied to the satellite images from 2001, 2011, and 2021 to generate diverse maps of LULC. Secondly, a household survey dataset was used to investigate influential factors. Approximately 220 households were interviewed in order to collect socio-economic information (including data on population growth, increased business activities, location of the area, agriculture land expansion, and need for settlement land). Household survey data was analyzed by using SPSS. Descriptive statistics, including frequency distributions and percentages, were applied to observe characteristics. Additionally, a binary logistic regression model was used to analyze the socioeconomic factors related to LULC change in DNPF. Key findings indicated a decline in natural forest areas within the study site. Specifically, both dry dipterocarp forest (−11.35%) and mixed deciduous forest (−0.18%) decreased from 2001 to 2021. The overall accuracy of the LULC maps was 94%, 86%, and 89% for the years 2001, 2011, and 2021 respectively. In contrast, agricultural land increased significantly by 155.70%, while built-up land, and water bodies increased by 65.54% and 35.33%, respectively. The results also highlighted a significant increase in construction land, up to 65.54%. Furthermore, the study found a correlation between agricultural expansion and a reduction of forest areas, along with an increase in built-up land along the forest areas’ boundaries. Timber exploitation and charcoal production also contributed to the decline in forest cover. The logistic regression model identified significant determinants of LULC change, including the area’s location, agricultural land expansion, increased business activity, and the need for settlement land. These factors have influenced the management of DNPF. Urgent sustainable management practices and actions, including forest ecosystem protection, village agricultural zoning, water source and watershed protection and public awareness, are required to preserve the forest areas of DNPF.

Circulation of Development Factors Promoted by Innovation of Land Management Under Background of Rural Vitalization:A Case Study of Tengtou Village in Zhejiang Province,China

Land is the space carrier for the existence and flow of other development factors.Activating rural land and promoting the circulation of other development factors through land management innovation is necessary to realize rural vitalization.This paper identifies the connotation of factor flow in the rural vitalization context,the action mechanism of land management innovation to boost the flow of development factors,the issues and obstacles restricting factor circulation,and the realization mechanism of the flow of development factors in rural vitalization.Based on the analytic paradigm constructed in the paper,the successful practice of promoting the flow of development factors through innovative land management in a model village is examined.The results show that:1)the unreasonable systems characterized by the land use system in rural areas are the main obstacles causing circulation issues in development factors.It is essential to engage in comprehensive reform to break down these long-lasting obstacles to the smooth flow of development factors.2)The land should play a leading role in the circulation of development factors in the background of rural vitalization;the main purpose of land management innovation is to activate the land factor,thereby promoting the circulation of other factors.3)The activated land factor will act as a‘trigger’to promote capital and technology in rural settings and use capital and technology to attract the inflow of talents and the return of migrant workers,whereby the population factor will act as a‘catalyst’for the cultivation of rural culture,bringing about the integration of various development factors.4)The innovation of land use and management,increased funding,and new technologies have brought multiple talents to Tengtou Village.The high-frequency mutual feedback between the village’s own and the external development factors resulted in its successful integration of industrial development.

The Characteristics and Controlling Factors of Water and Heat Exchanges over the Alpine Wetland in the East of the Qinghai–Tibet Plateau

Alpine wetland is one of the typical underlying surfaces on the Qinghai–Tibet Plateau.It plays a crucial role in runoff regulation.Investigations on the mechanisms of water and heat exchanges are necessary to understand the land surface processes over the alpine wetland.This study explores the characteristics of hydro-meteorological factors with in situ observations and uses the Community Land Model 5 to identify the main factors controlling water and heat exchanges.Latent heat flux and thermal roughness length were found to be greater in the warm season(June–August)than in the cold season(December–February),with a frozen depth of 20–40 cm over the alpine wetland.The transfers of heat fluxes were mainly controlled by longwave radiation and air temperature and affected by root distribution.Air pressure and stomatal conductance were also important to latent heat flux,and soil solid water content was important to sensible heat flux.Soil temperature was dominated by longwave radiation and air temperature,with crucial surface parameters of initial soil liquid water content and total water content.The atmospheric control factors transitioned to precipitation and air temperature for soil moisture,especially at the shallow layer(5 cm).Meanwhile,the more influential surface parameters were root distribution and stomatal conductance in the warm season and initial soil liquid water content and total water content in the cold season.This work contributes to the research on the land surface processes over the alpine wetland and is helpful to wetland protection.

Characteristics and driving factors of abandoned cultivated land in the hilly regions of southern China:A case study in Longnan,Jiangxi Province

The abandonment of cultivated land in southern China was gradually obvious.This research aims to provide a reference for solving the abandonment of cultivated land in hilly regions and promote rural development in China.We examined Longnan county located in the hilly regions of southern China as an example,where abandoned cultivated land is very common.We analyzed its land use data with a field survey to identify the abandoned cultivated land and geospatial characteristics.From the two aspects of social and natural factors,we analyzed the factors driving cultivated land abandonment with the help of Geodetector.The results showed that in 2019,the total area of the abandoned cultivated land in Longnan county was 4,962.35 hm^(2),covering 39.51% of this region.Among the topographic factors,the abandonment rate is positively correlated with elevation and slope gradient,but not with slope direction.Among the land parcel conditions,the abandonment rate is positively correlated with the access to road network and cultivation distance from settlement.At the county level,the abandonment of cultivated land in study area was affected by multiple factors,among which,the direct factor was the reduction in the labor force,such as the decrease of farming laborers and the increase of female population,which made farming unsustainable.Changes in production factors also promoted transformations in farmers’motivation to engage in production,such as the decrease of grain crops and the increase of cash crops,which was the indirect factor affecting cultivated land abandonment.The development of the rural nonagricultural industry affected farmers’enthusiasm,such as the decrease of farming households,which was the fundamental factor leading to cultivated land abandonment in this area.

Spatiotemporal Pattern of Cultivated Land Pressure and Its Influencing Factors in the Huaihai Economic Zone, China

Cultivated land pressure represents a direct reflection of grain security. Existing relevant studies rarely approached the spatiotemporal pattern of cultivated land pressure or the spatial heterogeneity of its influencing factors from the level of economic zones.Taking the Huaihai Economic Zone(HEZ), China for case analysis, this study investigated the spatiotemporal pattern of cultivated land pressure in diverse periods from 2000 to 2018 based on a modified cultivated land pressure index and spatial correlation models. On this basis, it explored the influencing factors of the spatial differentiation of cultivated land pressure in the late stage of the study using geographical detector as well as multi-scale geographically weighted regression model. The results indicated that: 1) in the study period, the global cultivated land pressure index of the study area decreased gradually, but cultivated land pressure increased locally in a significant way, especially in the central and southern Shandong Province;2) the spatial pattern of cultivated land pressure manifested global clustering features. Hot and secondary-hot spots presented a narrowing and clustering trend, whereas cold and secondary-cold spots manifested a spreading and clustering trend;3) average slope, the proportion of non-grain crops, population urbanization rate, and multiple cropping index have significant effects on the spatial differentiation of cultivated land pressure. The former three factors were positively correlated with cultivated land pressure, and the last factor was negatively correlated with cultivated land pressure;and 4) the amount of cultivated land has increased in the central and southern Shandong Province through land consolidation which, nonetheless, failed to improve the grain production. In regards to major grain producing areas similar to the HEZ in China, the authors suggest that great importance should be given to the balance of the quality and quantity of cultivated land, the optimization of agricultural production factors and the rational control of non-grain crops, thus providing a powerful guarantee for grain security in China.

Spatiotemporal Evolution and Influencing Factors of Urban-rural Construction Land in Rural Industrialized Areas in China:Case Studies in Changyuan City and Xinxiang County of Henan Province

Since China’s reform and opening up in 1978,the acceleration of industrialization and urbanization in China had led to dramatic changes in the pattern of urban-rural land use.In this paper,we focused on the rural industrialized areas in central China(Xinxiang County and Changyuan City of Henan Province).We used the average nearest neighbor index,spatial statistical analysis,and a structural equation model to analyze the spatiotemporal evolution and influencing factors of urban-rural construction land based on multisource spatial data and survey data.The results showed that:1)from 1975 to 2019,the spatial distribution of urban-rural construction land in rural industrialized areas had evolved from homogeneous distribution to local agglomeration.In terms of comparative analysis of cases,the spatial distribution of urban-rural construction land in Changyuan City had shown a trend from diffusion to agglomeration,and Xinxiang County had overall shown a spatial change from homogenization to agglomeration and then to regional integration development.2)The hot spots with increased urban-rural construction land significantly expanded,and they had a high degree of spatial overlap with industrial development.Among them,Xinxiang County was concentrated in central and marginal areas,and Changyuan was mainly concentrated in central urban areas.3)From the evolution of spatial proximity of urban-rural construction land,rural industrialized areas generally decline,showing the characteristics of internal differentiation in the rate of change.4)Industrial development,social economy,the policy environment,and urban development played a positive role in promoting the expansion of urban-rural construction land in rural industrialized areas.To promote the optimal use of regional land and the integrated development of urban-rural areas,we should combine the advantages of regional endowment,formulate development strategies according to local conditions,and adjust the way that land is used in a timely manner.

Construction land expansion and influencing factors of typical river valley cities in Northeast China: Taking Jilin City as an example

Jilin City is a typical river valley city in Northeast China.In this paper,the authors studied the spatial and temporal expansion characteristics of the built-up areas in Jilin City from 1990 to 2020 using the analysis of expansion speed and strength,fractal dimension,barycenter coordinate transfer index and sector analysis.The ultimate-goal is to analyze the driving and restrictive factors that affect the spatial expansion of river valley cities.The results indicate that(1)the expansion speed of urban land in Jilin City has been re-latively slow in the past 30 years,while only slightly faster in 2010–2020;(2)in the spatial dimension,Jilin City mainly expanded to the south,then to the west,and extensive expansion has resulted in complex mor-phology with little stability and compactness;(3)the expansion is affected by multiple factors,of which the positive factor is industrial development,while the restrictive factors include natural factors,population loss,etc.This study provides a case for the formulation of land use policies and land space planning in river valley cities.

基于LMDI模型的土地利用碳排放时空差异及影响因素研究——以洞庭湖区为例

运用碳排放系数法和对数平均迪氏指数(LMDI)模型,对1996—2020年洞庭湖区土地利用变化、土地利用碳排放时空差异及其影响因素进行分析。结果表明:(1)土地利用变化整体呈现出“三增三减”特征,建设用地和未利用地的变化程度较为显著,水域和草地次之,耕地和林地的变化程度最小。(2)总净碳排放量呈不断上升趋势,碳排放高值区由中部转向西、东、南部,土地利用碳足迹压力指数始终大于1,以0.54的年均增幅不断上升。(3)人均GDP、单位GDP用地面积和单位土地碳排放强度是影响土地利用碳排放的主要因子,人均GDP和单位GDP用地面积分别成为促进和减缓洞庭湖区碳排放量增长的主要因素。

基于LUCC的生态系统服务价值时空演变——以祁连山区域为例

分析祁连山区域生态系统服务价值的时空变化特征,可为该区土地高效开发利用、生态恢复与保护机制的构建提供数据支撑。基于1980年、1990年、2000年、2010年和2020年的土地利用数据,运用改进的当量因子定量评估祁连山区域不同历史时期的生态系统服务价值,结合空间自相关及GIS空间统计方法,探究研究区不同乡镇的地均生态系统服务价值时空变化特征。结果表明:1)1980-2020年,研究区主要土地类型为未利用地、草地、林地、耕地,总覆盖率在93%以上。其中林地和未利用地面积减少,建设用地动态度变化最大。2)1980-2020年,祁连山区域生态系统服务总价值增加了170.8285×10^(8)元,其中草地、林地和水域的生态服务价值占78%,水文调节和气候调节的生态服务价值占60.14%。3)地均生态系统服务价值的空间正相关性较明显,空间集聚程度较高。高值聚集区有由增加向减少转变的趋势,低值聚集区逐年增加。4)1980-2010年,祁连山区域南部生态系统服务价值高于北部,北部生态系统服务价值在2010年后有增加趋势,但研究区南北间生态系统服务价值还未达到均衡和稳定。

黄河流域两大区域的土地生态安全动态评价及比较

[目的]探究山东半岛与黄河几字弯两大区域的土地生态安全水平差异,为实现黄河流域生态保护与高质量发展,推动“共同抓好大保护,协同推进大治理”战略提供现实依据。[方法]运用熵值法、核密度估计、马尔科夫链与障碍因子模型等方法,对黄河流域两大区域的土地生态安全进行动态评价。[结果](1)在水平变化上,两大区域的土地生态安全增速均呈“倒U”形态势,山东半岛的土地生态安全水平明显高于黄河几字弯,但黄河几字弯的增长速度更快。(2)在时间上,两大区域土地生态安全均呈现“单核”演变特征,山东半岛区域差异有扩大态势,几字弯区域差异则有缩小态势。在空间上,两大区域均呈现出“东中部高—西部低”的空间分布态势。(3)动态演化特征上,两大区域土地生态安全等级演变具有“路径依赖”与“自身锁定”效应。(4)山东半岛土地生态安全受人均耕地面积、地均化肥农药施用量等影响;黄河几字弯土地生态安全受景观破碎度、森林覆盖率等影响。[结论]未来山东半岛与黄河几字弯既要根据区域优势分类施策,也要从流域全局出发,协同提升黄河流域土地生态安全水平。

农地流转提升了农业绿色全要素生产率吗?

在2006-2021年中国30个省份的面板数据基础上,本文通过SBM-GML超效率模型测算中国各省份农业绿色全要素生产率。采用双向固定效应模型和工具变量模型等方法,实证分析农地流转和农业绿色TFP之间的内在联系,并分析其影响路径机制。研究发现,中国农业绿色全要素生产率能够持续增长的主要原因在于技术进步。而农地流转能够推动农业绿色全要素生产率增长则是得益于技术效率改进。从异质性分析来看,农地流转对农业绿色全要素生产率增长的促进作用最显著的是东部地区和非粮食主产区,但在西部地区却正好相反。因此,中国应当加快推进农地流转工作进展,促进农业生产和经营管理模式变革,加快研发、推广和应用农业绿色生产技术,构建区域协作互助机制促进地区交流,进而促进农业绿色全要素生产率的提高。

东北三省耕地利用格局变化对粮食全要素生产率的影响

耕地是粮食生产最基本的要素,当前粮食需求扩大与粮食生产区域性不足矛盾突出,寻求更合理的耕地利用格局来实现粮食全要素生产率的提升具有重要意义。本研究基于土地利用/土地覆被变化(LUCC)遥感监测数据,应用GIS软件提取东北三省2000、2005、2010、2015年耕地利用格局相关数据,同时运用数据包络分析模型估算了2000、2005、2010年和2015年东北三省区域和市域粮食全要素生产率。在耕地利用格局变化分析和粮食全要素生产率测算的基础上,从耕地利用格局变化的角度选取指标构建面板数据模型,定量分析其对粮食全要素生产率的影响。结果表明:东北三省市域粮食全要素生产率4个时期均值分别为0.81、0.78、0.82和0.83,粮食全要素生产率空间分布从最初的相对均匀到局部集聚;耕地转出率和耕地斑块破碎度与粮食全要素生产率呈负相关关系,耕地面积比例、耕地转入率和耕地斑块聚合度与粮食全要素生产率呈正相关关系;东北三省粮食全要素生产率提高主要源于耕地面积增加、林地和未利用地向耕地的转入以及耕地在流域的聚合,粮食全要素生产率的降低主要源于耕地转入减少和建设用地对耕地的嵌入式占用。研究表明,严格规划耕地利用格局、持续开展土地整理、提高耕地聚合度,可在保证耕地有效数量的同时,提高耕地利用格局的集聚性和合理性,促进粮食全要素生产率的提升。

基于一种土地利用变化新指标的土地利用变化影响因素分析——以大兴安岭林牧交错区为例

研究土地利用变化机制,是保障生态脆弱区生态环境良性发展的必然要求。基于土地利用信息图谱构建新指标——土地利用转换度,借助土地利用转移矩阵和土地利用转换度刻画1990—2021年研究区土地利用转移的宏观特征,构建渔网提取土地利用转换度,分析其空间自相关性,并用地理加权回归(GWR)分析研究区土地利用变化的影响因素,为林牧交错区社会经济发展服务。研究发现:(1)1990—2021年,研究区土地利用类型的宏观格局变化不大,林地和草地是该区域的主要用地类型,林地主要分布在东部和北部的山区,草地主要分布在西南部,耕地主要分布于山地和草原交接的地区及河谷地带。(2)1990—2021年林地呈现增加趋势,草地逐年减少,耕地和建设用地缓慢增加。(3)草地、耕地和林地是该地区土地利用变动的主要类型,以草地转出最多,主要转换为林地和耕地。(4)土地利用转换度有显著空间自相关,存在明显的高高聚集和低低聚集。转换频繁区呈倒“C”字形,分布在大兴安岭西部山区与草地过渡带,即海拔700~900 m的地带。(5)GWR分析发现坡度、气温变化、人均GDP变化是影响该区土地利用的主要因素,人均GDP增加会降低土地利用转换度,而其他因素增加会导致土地利用转换加速。(6)土地利用转换度是一种可靠的土地利用变化度量指标,能够将空间和时间融合反映土地利用状态的变化强度。

土地政策松绑与县域新型城镇化——来自农村宅基地改革的经验证据

以县域为重要载体的新型城镇化是实现中国式现代化的必由之路,但随着农村剩余劳动力的不断外流,土地粗放利用、宅基地闲置甚至抛荒问题日益凸显。宅基地改革是促进土地要素与新型城镇化协调发展的重要举措,基于宅基地改革试点政策,运用多期双重差分法构造准自然实验,检验农村宅基地改革能否促进县域新型城镇化。研究发现:农村宅基地改革可以显著提升县域新型城镇化水平。政策路径识别发现,农村宅基地改革从非农就业、产业结构升级和激发市场潜能三方面提升县域新型城镇化水平。异质性研究表明,行政区划上,农村宅基地制度改革对于县、县级市和市辖区的新型城镇化水平提升能力呈现递增趋势;地区差异上,农村宅基地制度改革的政策效应在东部、中部地区县域得到有效发挥,对西部地区县域新型城镇化水平提升效果有限。通过土地政策改革推进以县域为载体的新型城镇化提供了经验证据,同时也从经验上就如何稳慎推进农村宅基地改革试点提供政策启示。

大汶河流域土地利用时空演变分析及生态空间多情景模拟

多情景模拟土地利用演变为大汶河流域土地管理和推动区域高质量发展提供参考。基于大汶河流域1990、2000、2010和2020年土地利用数据,借助动态度和土地利用转移矩阵分析研究区近30年来的土地利用时空演变特征和相关驱动机制,从地理环境、社会经济和交通路网三方面选取12个驱动因子,设置生态保护、耕地优先和经济发展3种情景,利用PLUS模型模拟研究区2030年土地利用空间分布及对比分析各情景模拟差异。结果表明:①近30年来,耕地面积减少明显,达630 km^(2);建筑用地面积持续增长且增幅较大,占比从8.8%增至16.7%。②2020年土地利用模拟结果Kappa系数为0.89,总精度为93.15%,均高于标准,PLUS模型满足大汶河流域土地利用模拟要求。③综合3种情景模拟结果发现,耕地优先情景下,耕地面积总量得到有效保护,相对限制建筑用地面积的增长,同时生态环境和经济建设都得到较好保障。因此耕地优先情景更符合大汶河流域可持续发展的要求。

土地要素市场化改革能够提升企业生产效率吗?——基于工业用地市场化改革的准自然实验研究

深化土地要素市场化改革是提升全要素生产率、促进高质量发展的重要途径。基于微观企业视角,利用双重差分模型探究工业用地市场化改革对企业全要素生产率的影响,并从资源利用、资源配置和技术创新3个方面,探究具体的影响机制。结果表明:在研究期内,工业用地市场化改革整体上促进了企业全要素生产率提升约14%;对企业主体而言,规模越小、所属行业土地依赖程度越高,则全要素生产率的提升效果越明显;分区域来看,东北及西部地区企业生产效率的提升作用显著高于东部地区。进一步从中介效应看,该改革可以通过资源配置和技术创新来促进企业全要素生产率的提升;而资源利用机制并未发挥显著作用。综上,继续深化工业用地市场化改革,并着力优化土地资源在企业间的配置,提高企业技术创新水平,有利于企业生产率的提升。

严控“溢价率”条件下住宅用地定价影响因素研究

土地市场是全国统一大市场的有机组成部分,地价管理是土地市场建设的核心工作之一。文章从土地的商品属性和特征价格出发,阐述了不完全竞争状态下的地价波动现象,强调了建立要素市场价格异常波动调节机制的必要性。基于评估方法交叉混淆、评估参数偏差不当、权重选取主观随意、土地评估对未来房价走势及库存和销售情况不敏感等问题,分析了土地评估的局限性。结合严控“溢价率”政策对住宅用地定价的更高要求,指出政府在确定土地出让价格时需一并考虑土地出让底价与15%“溢价率”之间的上下限关系。研究认为:确定住宅用地出让价格是一项复杂而庞大的系统工程,并非由单一因素决定,除参考土地评估价格以外,还应重视土地储备成本、土地出让计提、土地隐性成本、出让年度计划、土地使用强度、地价房价关系、房屋去化周期等7种因素对土地出让价格的影响。在此基础上,将土地出让成本的硬性约束作用、土地供应的政策导向作用、房地联动的产业关联作用纳入住宅用地价格形成机制之中。

东北地区耕地绿色利用效率测算及影响因素

推动东北地区耕地绿色利用是践行绿色发展理念、促进黑土地保护的重要途径。综合运用包含非期望产出的超效率SBM模型、Tobit模型对东北地区40个地级市2012~2021年耕地绿色利用效率的时空分布格局及影响因素进行定量测度。结果表明:①2012~2021年,东北地区整体耕地绿色利用效率较高,而东北各地区效率自2018年后开始呈现波动下降态势,2020年后有所回升;②东北地区耕地绿色利用效率空间差异性显著,分布格局随时间的推移而逐渐变化,在研究期内呈现出“东高西低”“四周高、中间低”“南北高、四周低”的演变特征;③粮食作物轮作面积比例、单位农作物播种面积农业机械总动力对东北各地区耕地绿色利用效率具有显著性负向影响,科技发展水平具有显著性正向影响,但是在不同地区,不同因素的影响强度存在一定差异。建议既要在政策制度上规范和引导,还应在技术上支持和赋能,通过实际措施提高东北地区耕地绿色利用效率,实现黑土地可持续利用。